package STUDENT.TRANDAODAIVI.QUESTION;


public class QuackBehavior2 {
	public void quack(){};
}

class Quack2 extends QuackBehavior2{
	public void quack(){
		System.out.println("Quack");
	}
}

class Squeak2 extends QuackBehavior2{
	public void quack(){
		System.out.println("Squeak");
	}
}

class MuteQuack2 extends QuackBehavior2{
	public void quack(){
		System.out.println("No-sound");
	}
}